Free South Dakota Self-Employed Tax Calculator 2025
Calculate your combined federal and South Dakota state income tax as a self-employed individual in 2025. Includes Self-Employment (SE) Tax at 15.3%, federal income tax (Schedule C / Form 1040), and South Dakota state income tax (No state income tax).
Federal Self-Employment Tax (2025)
- SE Tax: 15.3% (12.4% Social Security + 2.9% Medicare) on 92.35% of net profit
- Social Security wage base: $176,100 (2025)
- Half of SE Tax is deductible above-the-line on Schedule 1
- QBI deduction: up to 20% of qualified business income (Section 199A)
- Standard deduction: $15,750 (Single) / $31,500 (MFJ) for 2025
Filing Deadlines
Annual deadline: April 15 (extension to October 15 available via Form 4868). Quarterly estimated tax (Form 1040-ES): Q1 Apr 15, Q2 Jun 15, Q3 Sep 15, Q4 Jan 15.
South Dakota — No State Income Tax
No state income tax in South Dakota.